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DAVID ENSOR, CNN CORRESPONDENT (voice-over): It was the central pillar in the argument for preemptive war.

RICHARD CHENEY, U.S. VICE PRESIDENT: Simply stated, there is no doubt that Saddam Hussein now has weapons of mass destruction.

ENSOR: The United States put its credibility on the line.

COLIN POWELL, FORMER U.S. SECRETARY OF STATE: What we're giving you are facts and conclusions based on solid intelligence.

ENSOR: But much of that intelligence turned out to be wrong.

UNIDENTIFIED MALE: It was the lowest point in my life. I wish I had not been involved.

ENSOR: Tonight, an inside look at what went wrong and why.

UNIDENTIFIED MALE: Who is to blame? No question, it's the intelligence community. We did it to ourselves.

UNIDENTIFIED MALE: The problem is the White House didn't go to the CIA and say, tell me the truth, it said give me ammunition.

UNIDENTIFIED MALE: We can't afford to be wrong a second time. How many people in the world are going to believe us when we say it's a slam dunk, Iran has nuclear weapons?

ENSOR (on camera): "Dead wrong." That's how the commission appointed by President Bush describes U.S. intelligence in the lead up to the Iraq War. Welcome to CNN PRESENTS. I'm David Ensor.

Despite public warnings before the war, no weapons of mass destruction have been found. But the commission's searing report left unanswered a critical question. Should anyone be held accountable? Tonight, we go behind the scenes in search of answer and for the first time we hear from key players, on camera and on the record, who were there when some of the mistakes were made.

(voice-over): In early 2001, George W. Bush, urged by his father, who had been a director of central intelligence, keeps George Tenet in charge of the CIA. The new president is applauded for putting the agency above politics. And Tenet, who was appointed by Bill Clinton, becomes the first CIA director in more than three decades to survive a change of party in the White House.

But theirs will be a fateful relationship. The president will take the country to war, a decision he will justify using intelligence produced by Tenet's CIA.

In 2005, as the Iraq War entered its third year, the top U.S. weapons hunter ended his search. Case closed. No weapons of mass destruction have been found.

The harm done to American credibility by our all too public intelligence failings in Iraq, reports the commission appointed by the president to investigate the failures, will take years to undo.

GEORGE W. BUSH, U.S. PRESIDENT: To win the war on terror, we will correct what needs to be fixed.

ENSOR: The commission found no sign that the evidence had been shaped by political pressure, it was simply wrong.

BUSH: The central conclusion is one that I share, America's intelligence community needs fundamental change.

ENSOR: But like earlier congressional investigations, the president's commission looked only at the intelligence, not how the commander-in-chief and his top aides used it to make the case for war.

DAVID GREGORY, NBC CORRESPONDENT: Did this commission not ask the tough questions? Did they not challenge some of these assumptions? And doesn't ultimate responsibility rest with the president of the United States?

JUDGE LAURENCE SILBERMAN, COMMISSIONER: We had discussions with the president. We didn't interview the president, nor did we interview the vice president.

ENSOR: So what may be the last official review of how the mistakes were made gives policymakers a pass.

SILBERMAN: Our job was to look at the intelligence that came from the intelligence community.

ENSOR: The commission's 600 page report directs most of its fire at the Central Intelligence Agency, starting at the top.

UNIDENTIFIED MALE: Mr. Tenet, would you stand and raise your right hand. ENSOR: When he was named director of central intelligence in 1997, George Tenet was the fifth DCI in six years. He promised to tell truth to power.

GEORGE TENET, FORMER DIRECTOR OF CENTRAL INTELLIGENCE: To the president and all those who rely on our nation's intelligence capabilities, I will deliver intelligence that is clear and objective and does not pull punches. To the Congress ...

ENSOR: Tenet inherited an agency grappling with changing threats in a post Cold War world. And still coming to grips with the fact that it had missed Saddam Hussein's push to build a nuclear weapon in the months before the Gulf War.

After Saddam's defeat, United Nations inspectors investigated and destroyed his nuclear program, along with most of his chemical and biological weapons.

But when they departed in 1998, the U.S. lost its window into Iraq.

Iraq was not the only intelligence black hole.

The CIA chief had warned urgently and often that a terror attack was coming, but the intelligence community had no idea when or where. In the days after what some labeled the greatest intelligence failure since Pearl Harbor, there were calls for George Tenet's resignation.

But during a morale-boosting visit to the CIA, President Bush will make clear that as the United States launches its war on terror, he wants George Tenet at his side.

MICHAEL SCHEUER, CIA ANALYST: The CIA is, at the end of the day, the peculiar instrument of the executive branch and the president.

ENSOR: Michael Scheuer was a long time CIA analyst who wrote a book under the pseudonym "Anonymous," critical of CIA leadership in the war on terror.

SCHEUER: But under Mr. Tenet it became very much focused on the president. He was called the "First Customer" and clearly became the be all and end all of our efforts.

JOHN MCLAUGHLIN, FORMER ACTING DIRECTOR OF THE CIA: There is always a danger in the intelligence business of getting too close to the policymaker.

ENSOR: John McLaughlin was Tenet's second in command. He is now a CNN analyst.

MCLAUGHLIN: But if you aren't close enough to understand what they're thinking and how they're operating and what their requirements are, you're not going to serve them well.

ENSOR: The day after the towers fall, attention is focused on launching an attack on al Qaeda and its Taliban protectors in Afghanistan, but inside the White House sites are also set on another target, Iraq.

In the spring of 2002, Vice President Cheney, who had been secretary of defense when the U.S. discovered Saddam's WMD programs in 1991, travels from the White House to CIA headquarters in Virginia. He beings to press analysts on the intelligence assembly line.

JAMES PAVITT, FORMER CIA DEPUTY DIRECTOR OF OPERATIONS: Policymakers love intelligence when it supports their policy and they have difficulty with intelligence when it does not.

ENSOR: James Pavitt was chief of the CIA's cover spying operations.

PAVITT: The role of the intelligence officer is to produce the intelligence and to objectively and honestly table it. If pushed, now are you sure that's right? That's fine, there's nothing wrong with that.

ENSOR: Robert Baer, a legendary CIA field officer served most of his 21 year career in the Middle East. He left the agency in 1997.

ROBERT BAER, FORMER CIA OFFICER: I think Cheney, as far as I can reconstruct this, everybody knows that Saddam's got weapons of mass destruction. The French do, the British do, even the Russians thought he did. Tell us what's your best stuff.

ENSOR: The overwhelming Washington consensus was that Saddam would not have abandoned his drive for weapons of mass destruction.

PAVITT: And there was a whole panoply of reasons to believe that was the case. There are not many countries in the world that have used weapons of mass destruction on their own people. Iraqis did.

ENSOR: At the Pentagon, Secretary of Defense Donald Rumsfeld sets up a special office to provide him with alternative intelligence analysis, focusing on a possible link between Saddam and al Qaeda. The Pentagon unit is not mentioned by the president's commission.

LARRY JOHNSON, FORMER STATE DEPARTMENT OFFICIAL: They even briefed their findings to the community and the community would come back and say, wait a second, you don't know what you're talking about. That's garbage. That's misleading, that misrepresents.

ENSOR: Larry Johnson was a counterterrorism official in the State Department and the CIA before leaving government in 1993.

JOHNSON: And then they would take the same brief or an even more extreme version and brief it directly to people like the vice president.

ENSOR: The spies called it cherry-picking, choosing scraps of intelligence to prove a worst-case scenario.

July 23rd, a senior British intelligence officials briefs Prime Minister Tony Blair on his recent discussions in Washington. According to notes on the Downing Street briefing, the MI6 chief reported that President Bush wanted to remove Saddam through military action. The intelligence and facts, he said, "were being fixed around the policy."

The White House declined interview requests for this report. President Bush addressed the memo at a recent news conference with Blair.

BUSH: Somebody said, well, we had made up our mind to go -- to use military force to deal with Saddam. There is nothing farther from the truth. My conversation with the prime minister was how could we do this peacefully.

ENSOR: But in the summer of 2002, the White House Iraq Group, WHIG, had quietly begun a campaign to build support for war. National Security Adviser Condoleezza Rice, Karl Rove and Karen Hughes and the chiefs of staff to both the president and the vice president planned strategy in weekly meetings.

CHENEY: Simply stated, there is no doubt that Saddam Hussein now has weapons of mass destruction.

ENSOR: Late August, vice president Cheney takes the lead in public, escalating the rhetoric against Saddam.

CHENEY: The Iraq regime has, in fact, been very busy enhancing its capabilities in the field of chemical and biological agents and they continue to pursue the nuclear program they began so many years ago.

GREG THIELMANN, FORMER STATE DEPARTMENT OFFICIAL: That speech it seemed to me was basically a declaration of war speech.

ENSOR: Greg Thielmann was in charge of monitoring WMD at the State Department's bureau of intelligence.

THEILMANN: That's when I, for the first time, became really alarmed about where we were going on this.

CHENEY: But we now know that Saddam has resumed his efforts to acquire nuclear weapons.

ENSOR: The CIA has no new proven evidence to support the vice president's claims.

MCLAUGHLIN: We did not clear that particular speech. As controversy developed in the course of debate over Iraq, we began to clear speeches later, but at that point we were not clearing speeches like that.

ENSOR: By September, the Pentagon has quietly positioned forces in countries around the Persian Gulf. The United States will be ready to move against Saddam in as little as 60 days.

SHEUER: There was just a resignation within the agency that we were going to war against Iraq and it didn't make any difference what the analysis was or what kind of objections or countervailing forces there were to an invasion. We were going to war.

ENSOR: Intelligence analysts worked in an environment, the president's commission reports, that did not encourage skepticism. It is the single, brief description of Washington in 2002 when the intelligence mistakes were made.

(COMMERCIAL BREAK)

ENSOR: Early every morning, the president of the United States received a super secret briefing from the CIA, the only agency in the intelligence community that answered directly to him.

George Tenet's plainspoken style appealed to the new president, so Bush insisted Tenet brief him face to face.

Some of the CIA's briefings on Iraq begin to rely on one analyst, an engineer with limited nuclear weapons experience, known only as Joe T. He believed he had found the smoking gun. Saddam was buying high strength aluminum tubes that Joe T. insists are meant for centrifuges to enrich uranium.

THIELMANN: Of all the pieces of evidence, this was potentially the most damning, would be the kind of thing, through uranium enrichment, get enough fissile material for a nuclear weapon.

ENSOR: The three feet by three inch tubes are the only piece of physical evidence that might suggest a bomb building program.

THIELMANN: We were really agnostic at the beginning of it but we listened to the experts and more and more evidence came in that told us, no, this can't be true.

ENSOR: Nuclear experts at the Department of Energy argued the tubes are the wrong size and material for use in centrifuges but exactly right for rocket casings. They called Joe T.'s reasoning improbably.

CARL FORD, FORMER STATE DEPARTMENT INTELLIGENCE OFFICIAL: Why would you immediately jump to the conclusion that these were for their nuclear program?

ENSOR: Carl Ford was assistant secretary of state in charge of the department's bureau of intelligence.

FORD: Once an analyst starts believing their own work and quits doubting themselves and starts saying, I'm going to prove to you that they've got nuclear weapons, watch out. Be on your alert.

ENSOR: On Sunday, September 8th, the lead story in the "New York Times" quotes anonymous officials who maintain the tubes are intended for enriching uranium. "The first sign of a smoking gun," the unnamed officials argue, "may be a mushroom cloud."

UNIDENTIFIED MALE: I would call it official leaking because I think these were authorized conversations between the press and members of the intelligence community that further misreported the nature of the intelligence community's disagreement on this issue.

ENSOR: Some top officials had been advised of the sharp disagreement, but in coordinated appearances on the Sunday talk shows, the administration reveals no doubts.

CONDOLEEZZA RICE, U.S. SECRETARY OF STATE: High quality aluminum tubes that are only really suited for nuclear weapons programs, centrifuge programs.

CHENEY: I do know with absolutely certainty that he is using his procurement system to acquire the equipment he needs to enrich uranium to build a nuclear weapon.

DONALD RUMSFELD, U.S. SECRETARY OF DEFENSE: Imagine a September 11 with weapons of mass destruction.

RICE: We don't want the smoking gun to be a mushroom cloud.

RAND BEERS, FORMER NSC OFFICIAL: As they embellished what the intelligence community was prepared to say and as the press reported that information, it began to acquire its own sense of truth and reality.

ENSOR: Rand Beers will resign his White House post and later work against the reelection of President Bush.

The nuclear menace from Iraq has been planted in the public's mind. Rumsfeld's Pentagon unit pushes a second threat, a connection between Iraq and al Qaeda.

SHEURER: Mr. Tenet, to his credit, had us go back through CIA files and we went back for almost 10 years, reviewed nearly 20,000 documents, which came to 65,000 pages or more and could find no connection in the terms of a state sponsored relationship with Iraq. I believe Mr. Tenet took it downtown, but it apparently didn't have any impact.

RICE: Clearly, there are contacts between al Qaeda and Iraq that can be documented. There clearly is testimony that some of these contacts have been important contacts and there's a relationship here.

RUMSFELD: We have what we consider to be credible evidence that al Qaeda leaders have sought contacts in Iraq who could help then acquire weapons of mass destruction capabilities.

ENSOR: In fact, CIA intelligence notes "critical gaps" in the evidence because of the "questionable reliability" of many of its sources.

September 12th, on the day after the first anniversary of the 9/11 attacks, President Bush will address the United Nations.

BUSH: And our greatest fear is that terrorists will find a shortcut to their mad ambitions when an outlaw regime supplies them with technologies to kill on a massive scale.

Saddam Hussein's regime is a grave and gathering danger.

ENSOR: Seven days later, the president will ask Congress to grant him authority to use any means he decides necessary against the perceived threat from Iraq. That includes military force.

(COMMERCIAL BREAK)

ENSOR: Congress has been asked to give the president authority to launch a preemptive strike before Iraq openly threatens or attacks the United States.

SEN. TRENT LOTT, (R) MS: ... conclusion, we will have set in motion the beginning of the end of Saddam Hussein.

ENSOR: That means the decision to go to war will be based on secret intelligence.

SEN. JON KYL, (R) AZ: And that debate needs to be based upon the very best information, the very best intelligence ...

ENSOR: There is enormous pressure to get it right.

ARLEN SPECTER, (R) PA: ... authorize the use of force, the equivalent of a declaration of war. There is no congressional responsibility that is weighted more ...

SEN. RICHARD DURBIN, (D) IL: As we drew closer to the day of the vote, it stuck me as odd that we had never asked for a national intelligence estimate, an NIE. That national intelligence estimate draws together all the intelligence agencies and says, now, what's our best information about the threat and what we will face if we invade.

ENSOR: Members of the Senate Intelligence Committee demand that George Tenet, as director of central intelligence, produce an NIE before the Congress votes.

MCLAUGHLIN: I do recall thinking that it's unusual to get a request from the Congress for a national intelligence estimate. Normally that request comes through the administration.

DURBIN: Totally unusual. The agencies understand that if we're about to take a major military action or even consider one, you bring all your intelligence agencies together and say, what do you know, and what do you know for sure before we put our troops in harms way. Before we risk the reputation and treasure and bodies of our servicemen. What do we know?

And the administration didn't do that.

ENSOR: Tenet must now present the intelligence community's formal judgment on matters White House officials have already publicly addressed.

THIELMANN: On some of the critical assessment, especially Iraq's nuclear weapons capabilities, one found that Tenet was defending very stubbornly the erroneous CIA interpretation. ENSOR: Resolving the conflict over the aluminum tubes comes down to one final meeting. The Department of Energy and the State Department argue they are not for a nuclear program. The CIA lobbies the other agencies at the table, insisting they are.

UNIDENTIFIED MALE: The Department of Energy was present but did not have the right individual there to argue the case. So when confronted with the data, this individual was not quite prepared to say, well, let me lay out all of the technical reasons why we would have a different view. It's one of those elements of life and bureaucracy that intervened at a critical moment to make a difference in what the final product said.

ENSOR: Life and bureaucracy lead to a majority vote against the nuclear experts at Energy and the skeptics at State in favor of the CIA's analysis of the tubes.

FORD: I would have felt much more comfortable if I had thought that the majority view was correct. And I didn't. So that I thought that the United States and the president in particular, were taking a terrible risk that they were going to go to war in Iraq and the intelligence community would have pushed them in that direction.

ENSOR: The tubes become primary evidence for the NIE's key judgment that Saddam is reconstituting his nuclear program.

UNIDENTIFIED MALE: We couldn't really buy on to any of the things being said so the State Department's intelligence bureau put in a very deliberate and strong and lengthy dissent.

ENSOR: The State Department lays out its doubts about the tubes, calls "highly dubious" the claim that Iraq is trying to buy uranium in Africa and refuses to predict when Saddam's alleged nuclear program might yield a bomb.

UNIDENTIFIED MALE: I think that it would have been more accurate for the intelligence community to say we don't know exactly what's going on there and there are some indications that they may be working on their nuclear program again, but don't ask us to go up there and prove that to anybody, because it is mostly guesswork on our part.

BAER: And the problem is the White House didn't go to the CIA and say "tell me the truth." It said, "give me everything you've got. Give me ammunition."

This is not peculiar to this White House. Pick a policy, go to the intelligence agencies, get your talking points.

UNIDENTIFIED MALE: There as no more than the normal political pressure from policymakers. I think the intelligence community was so certain of its findings that it didn't require any political pressure from the policymakers.

SCHEUER: I had never seen a document quite like it in terms of an NIE but to produce it in such a short time suggests something -- either the evidence was overwhelming or the political imperative was overwhelming.

ENSOR: Vice President Cheney, who declined an interview request for this report, addressed the question of political pressure on CNN's WOLF BLITZER REPORTS.

CHENEY: The WMD commission looked at that very carefully and found not a shred of evidence to support it. There never was because they never had it.

ENSOR: 10:30 p.m., October 1st, 2002. The 92-page NIE is delivered to the Senate Intelligence Committee. The next morning, Deputy Director McLaughlin briefs the committee in secret session. He is specifically asked whether there is evidence Saddam would give weapons of mass destruction to al Qaeda.

MCLAUGHLIN: The point we made to the NIE was he would only provide weapons and material support to terrorists to attack the United States if he was cornered.

ENSOR: Which meant the NIE did not conclude the threat from Saddam was imminent.

DURBIN: I walked out of those hearings having heard something that was truthful and accurate and picked up the newspaper and saw someone from the White House or administration has just said the opposite, or they've said it much differently. I am bound by law not to go to the press and say, something's wrong here. I can't do it.

ENSOR: To force the information that contradicts administration claims into the open, the intelligence committee insists that Tenet produce a declassified NIE. Instead the CIA director releases a document that mirrors in tone a white paper written earlier by the White House Iraq group. Contradictory evidence is played down. Claims that strengthen the case for war are emphasized.

October 7th, three days before the Congress is to vote.

BUSH: Alliance with terrorists could allow the Iraqi regime to attack America without leaving any fingerprints. Facing clear evidence of peril, we cannot wait for the final prove. The smoking gun that could come in the form of a mushroom cloud.

UNIDENTIFIED FEMALE: The ayes are 77, the nays are 23. The joint resolution is passed.

DURBIN: The intelligence agencies failed in the most important responsibility. Advising a president before the decision is made to go to war. I think that if Mr. Tenet felt the intelligence was bad or misleading, he should have resigned over it.

BEERS: Unless you are prepared to resign, it is very difficult to continue to tell the president something that he doesn't want to hear. Because if you're not prepared to resign, you're also not prepared to be fired.

ENSOR: At the time, George Tenet stood behind the findings of the NIE and stayed on. He had gained a place in the president's war cabinet.

(COMMERCIAL BREAK)

ENSOR: Saturday, December 21st, 2002, the decision to order the invasion of Iraq is looming. George Tenet and John McLaughlin brief the president, the vice president and the national security adviser. And according to Bob Woodward's book, "Plan of Attack," McLaughlin presents the case on weapons of mass destruction as it might be presented to a jury with top secret clearances.

Unconvinced, President Bush complains it's not something that Joe Public will understand. According to what the president then told Woodward, Tenet then assures him it's a slam dunk.

Tenet has confirmed he spoke those words in the Oval Office that day but has not confirmed the context. He now declines all interviews.

MCLAUGHLIN: I make a habit of never talking about anything that's happened in the Oval Office, particularly while a president is in office. What I would tell you is that I don't think "slam dunk," as it has been described, is the right way to characterize George Tenet's total view of the Iraq WMD program, or the Iraq WMD problem. There was -- I think it was an oversimplification of how he would think about it.

ENSOR: At the time, in fact, the WMD evidence was falling apart. Undercut by the CIA's own reporting and the fact that UN inspectors in Iraq had not found any weapons.

In the weeks before the president's State of the Union address, White House speechwriters search for something concrete to prove Saddam is trying to build a nuclear bomb. With only days to go, a year old piece of evidence that the CIA cannot confirm is pulled off the shelf.

BUSH: The British government has learned that Saddam Hussein recently sought significant quantities of uranium from Africa.

ENSOR: The 16 word indictment inserts a claim Tenet himself had kept out of the president's speech on the even of the congressional vote for war.

MCLAUGHLIN: There were reservations that everyone had about this reporting on uranium from Niger and that we had serious concerns about whether it was true. Now, how it got in there I don't know and that is yet to be determined.

ENSOR: In fact, the Senate Intelligence committee would report there had been a last minute dispute between the White House and the CIA over the allegation. When the president's speechwriters changed the script to cite British intelligence as the source, not the CIA, the senior agency analysts let it go.

BAER: It's just politicization. You keep on pounding on the CIA director and say, I'm not ask you to lie, just give us everything you've got.

ENSOR: A week later, Secretary of State Colin Powell will make the case for war in a speech to the United Nations.

POWELL: We also have satellite photos that indicate that banned materials have recently been moved from a number of Iraqi weapons of mass destruction facilities.

ENSOR: Powell will put America's credibility and his own on the line.

COL. LARRY WILKERSON, COLIN POWELL'S CHIEF OF STAFF: So he came through the door that morning and he had in his hand a sheaf of papers and he said this is what I've got to present at the United Nations according to the White House and you need to look at it.

WILKERSON: It was anything but an intelligence document. It was as some people characterized it later, some kind of Chinese menu from which you could pick and choose.

ENSOR: At the CIA, Powell and his aides questioned, point by point, the menu of charges drafted by the White House.

WILKERSON: There was no way the secretary of state was going to read off a script about serious matters of intelligence that could lead to war when the script was basically unsourced.

ENSOR: For four days and four nights in the conference room next to Tenet's office, they argued over the intelligence.

UNIDENTIFIED MALE: Secretary Powell asked a lot of questions, expressed skepticism about some, was reassured about others. If he was deeply skeptical it came it. If we were deeply skeptical it came out.

WILKERSON: And he turned to the DCI, Mr. Tenet, and he said, everything here, everything here, you stand behind. And Mr. Tenet said absolutely, Mr. Secretary. And he said, well, you know you're going to be sitting behind me tomorrow. Right behind me. In camera.

POWELL: What we're giving you are facts and conclusions based on solid intelligence.

ENSOR: For more than an hour Secretary Powell displays photos, holds up a chemical vial that suggests anthrax, shows slides, all to make dozens of claims about Saddam's weapons of mass destruction.

POWELL: I am not expert on centrifuge tubes but just as an old army trooper, I could tell you a couple of things. FORD: Every single thing we knew was thrown into that speech. This is all we got and we're making these firm judgments?

POWELL: One of the most worrisome things that emerges from the thick intelligence file we have on Iraq's biological weapons is the existence of mobile production facilities used to make biological agents.

ENSOR: He makes a dramatic accusation. Saddam has bioweapons labs mounted on trucks that would be almost impossible to find.

POWELL: We have firsthand descriptions ...

DAVID KAY, FORMER CHIEF CIA WEAPONS INSPECTOR: In fact, Secretary Powell was not told that one of the sources he was given as a source of this information had indeed been flagged by the Defense Intelligence Agency as a liar, a fabricator.

POWELL: To finding one ...

ENSOR: Powell was also not told that the prime source, an Iraqi defector, code named "Curveball" had never been debriefed by the CIA.

JOHNSON: Maybe the name of agent was alarming enough. Maybe it should have been "Screwup" or "A Lying Sack of Manure." Something like that. But to know that you're giving the president a ticket to go to war based on one source, at that point you want to drag the source in and talk to him yourself.

UNIDENTIFIED MALE: Curveball is a case of utter irresponsibility and a good example of how decayed the intelligence process has become.

ENSOR: The day before Powell's speech, a CIA skeptic had warned about the defector's reputation as a liar. In an e-mail reply, his superior acknowledges the problem but adds, "This war is going to happen regardless. The powers that be probably aren't interested in whether Curveball knows what he's talking about.

Powell was not told about the e-mail.

POWELL: Leaving Saddam Hussein in possession of weapons of mass destruction for a few more months or years is not an option. Not in the post September 11th world.

ENSOR: The speech would turn out to be riddled with misleading allegations but at the time the press plays it as an overwhelming success.

WILKERSON: He had walked into my office musing and he said words to the effect of, I wonder how we'll all feel if we put half a million troops in Iraq and march from one end of the country to the other and find nothing.

ENSOR: I will forever be known as the one who made the case, Colin Powell now says. I have to live with that.

WILKERSON: I look back on it and I still say it's the lowest point in my life. I wish I had not been involved in it.

ENSOR: March 19th, 2003. The aerial bombardment of Iraq begins. The first preemptive war on this scale in U.S. history.

(COMMERCIAL BREAK)

ENSOR: May 1st, 2003. The president declares that major combat in Iraq is over. But Saddam's weapons of mass destruction, the primary reason for going to war, have not yet been found.

George Tenet asks David Kay, who had been the chief UN nuclear inspector after the Gulf War to take charge of the search.

KAY: When I took on this job I had a set of conditions to do it because I was essentially taking on the moral hazard, as I've referred to it, for the CIA. That is, it was a CIA conclusion that there were weapons.

ENSOR: Once Kay is in Iraq, it is almost immediately clear to him that the WMD stockpiles he and his thousand strong team are searching for are not there. The aluminum tubes are an early signal.

KAY: We got in and found they really were part of a weapons program.

ENSOR: The bioweapons labs described by Curveball don't exist. In private e-mails, Kay begins to warn Tenet that the evidence is falling apart.

WILKERSON: George actually did call the secretary and say, I'm really sorry to have to tell you, we don't believe there were any mobile labs for making biological weapons. This was third or fourth telephone call and I think it's fair to say the secretary and Mr. Tenet at that point ceased being close.

You can be sincere and you can be honest and you can believe what you're telling the secretary, but three or four times on substantive issues like that, it's difficult to maintain any warm feelings.

ENSOR: There are also increasing questions about the president's State of the Union charge that Saddam was buying uranium in Africa.

RICE: And had there been even a peep that the agency did not want that sentence in or that George Tenet did not want that sentence in that the director of central intelligence did not want that in, it would have been gone.

ENSOR: When the White House blames Tenet, he takes public responsibility and so offers cover for the president. It is an old Washington pattern.

JOHNSON: The CIA was not the one who said hey, let's invade Cuba and launch the Bay of Pigs. That was a direction from Dwight Eisenhower and then it was continued by John Kennedy. The CIA wasn't the one who said, hey, let's go into Vietnam and set up assassination teams. Again, that direction came from Lyndon Baines Johnson. Hey, let's get involved and see if we can launch a coup in Chile. That came from Richard Nixon.

And when you come to Iran-Contra, that came from Ronald Reagan. And yet the CIA has become the convenient whipping dog that when things go back you've got to have somebody to kick, and they end up being the dog that gets kicked.

ENSOR: Behind the scenes, the ties of loyalty between President Bush and George Tenet begin to fray. And David Kay, after six months on the ground in Iraq is ready to quit. Tenet tells him, if you resign now, it will appear that we don't know what we're doing. That the wheels are coming off.

KAY: I was asked to not go public with my resignation until after the president's State of the Union address which -- this is Washington and in general -- I've been around long enough so I know in January you don't try to get bad news out before the president gives his State of the Union address.

It is time to give the fundamental analysis of how we got here ...

ENSOR: Eight days after the president's January 2004 State of the Union, David Kay testifies before the Senate Armed Services Committee.

KAY: My view was that the best evidence I had seen was Iraq indeed had weapons of mass destruction.

It turns out we were all wrong and that is most disturbing.

If the intelligence community had said there were no weapons there, would the policymakers have decided for other reasons, regime change, human rights, whatever, to go to war. All you can say is we'll never know, because the system said, apparently, it's a slam dunk there are weapons there.

ENSOR: Kay's testimony sparks another round of finger pointing and the right between the White House and the CIA breaks open.

TENET: Let me be clear. Analysts differed on several important aspects of these programs and those debates were spelled out in the estimate. They never said there was an imminent threat.

ENSOR: In his February speech, Tenet defends the agency and implicitly raised the question of how policymakers used the intelligence. A month later he is called before the Senate Armed Services Committee.

SEN. EDWARD KENNEDY, (D) MA: Did you ever tell him, Mr. President, you are overstating the case? Did you ever tell Condoleezza Rice, did you ever tell the vice president that they are overstating the case? And if you didn't, why not?

TENET: Well, senator, I do the intelligence. They then take the intelligence and assess the risk and make a policy judgment about what they think about it. SEN. CARL LEVIN, (D) MI: It seems to me there's got to be someone in your office who is going to say to you, you know, the vice president said something which just doesn't have our support.

TENET: Sir it's a fair point.

LEVIN: You can't just wait until we have a hearing ...

TENET: Sir, it's a fair point.

KENNEDY: Do you believe the administration, then, misrepresented the facts to justify the war?

TENET: No sir, I don't.

KENNEDY: Well, why not?

TENET: In policy judgments, you know, sir, there are places where I intervened ...

UNIDENTIFIED MALE: The great 18th director of central intelligence, the honorable George J. Tenet.

ENSOR: On June 3rd, 2004, George Tenet announced his resignation. His tenure included major successes. Unraveling Pakistani involvement in nuclear proliferation, convincing Libya to give up weapons of mass destruction. Hitting the ground running in Afghanistan within days of 9/11.

UNIDENTIFIED MALE: George Tenet drove that process. Clearly, the victories we've had in counterterrorism are ones that George Tenet deserves a great deal of credibility.

ENSOR: But when it came to the most important issue of his career, the war in Iraq, Tenet may be remembered for two words that could haunt him forever, "Slam dunk."

KAY: If you trade access and influence for independence and questioning, you're not serving either of the institutions you represent, the CIA or the president at whose pleasure you serve.

TENET: It has been the greatest privilege of my life to be your director. I thank you all very much.

ENSOR: Six months later, Congress will mandate the first major overhaul of the nation's intelligence system since 1947, when the Central Intelligence Agency was created.

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UNIDENTIFIED MALE: Ladies and gentlemen, the recipients of the Presidential Medal of Freedom.

ENSOR: Six months after George Tenet resigned, President Bush awarded him and two other officials who played key roles in America's involvement in Iraq the nation's highest civilian honor. The talk is now about regime change and building democracy, but no one has yet been held accountable for the flawed intelligence or the way it was used, the convince the American people of an urgent need for war.

As the fighting continues, other dangers intensify. The probability of nuclear weapons in North Korea, the possibility in Iran and the fear of loose nukes in the hands of terrorists.

KAY: We can't afford to be wrong a second time. How many people in the world are going to believe us when we say it's a "slam dunk," to use George Tenet's terms? Iran has nuclear weapons. The answer is going to be, you said that before.

JOHN NEGROPONTE, DIRECTOR OF NATIONAL INTELLIGENCE: From everything we've learned, from the experience we've had in the past several years, we don't want a repetition of this kind of situation. We don't want to have the Curveball situation.

ENSOR: John Negroponte is now at the storm's center. The nation's first ever director of national intelligence must take charge of 15 often competing spy agencies. Get it right on Iran and North Korea and find a way to ensure that dissent is heard.

MCLAUGHLIN: It isn't always pleasant to hear bad news, but the chief intelligence officer of the United States, as a job requirement, is frequently the skunk at the picnic, and that's just the way it is.

NEGROPONTE: Terrorism and WMD and that's certainly something -- and those are issues I'm going to devote ...

ENSOR: Negroponte has been handed vast responsibility but less defined power. Most of the agencies that make up America's intelligence community and 80 percent of its $40 billion budget have been controlled by the Pentagon.

WILKERSON: It is up to the president of the United States how effective or ineffective Ambassador Negroponte is as the national intelligence director. And he is going to have to make choices that fly in the face, in my view, of both his vice president and his secretary of defense. Which means he's going to have to stand up to them.

NEGROPONTE: I believe that the president deserves from his director of national intelligence and from the intelligence community the unvarnished truth.

ENSOR: John Negroponte promises to tell truth to power. But if he is willing to be the skunk at the picnic, will the president continue his stand behind him?

(END VIDEOTAPE)

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